How can I export every frame vertex animation data?
you can use for-loop to export every frame positions:
import bpy

sce = bpy.context.scene
f = open(&quot;props.txt&quot;, &quot;w&quot;)
for frame in range(sce.frame_start, sce.frame_end+1):
    sce.frame_set(frame)

    
    me = bpy.context.object.data   
    print(&quot;Frame %i&quot; % frame, file=f)     
    for v in me.vertices:
     print(v.co.xyz, file=f)
 
f.close()